Metal-working.



N. E. CLARK.

v METAL WORKING.

APPLICATION FILED AN.14, 1909.

Patented Jan. 4, 1916.

2 SHEETS-SHEET I.

H 1mg lNl/E/VTOI? Norris Elmore C'lcrr WITNESSES 2$ N. E. CLARK.

METAL WORKING.

APPLICATION FILED IAN. I4, 1909.

Patented J an. 4, 1916.

2 SHEETS-SHEET 2.

. INVENTOR Norris Elmore Clau- W/TNESSES v 8 NORRIS ELMOBE CLARK, OFPLAINVILLE, CONNECTICUT.

METAL-WORKING.

Specification of Letters Patent.

Application field January 14, 1909. Serial No. 472,260.

T all whom it may concern:

Be it known that I, NoRRIs ELMORE CLARK, a citizen of the United States,residing at Plainville, in the county of Hartford and State of.Connecticut, have invented certain new and useful Improvements in Metal-VVorking, of which the following is a specification.

This invention relates particularly to the art or method of makingreticulated metal plates or sheets commonly termed expanded metal.

My main object is to decrease the cost of manufacture and also toimprove the prod- 5 uct.

The machine and method of operation are such that the finished productmay be made in a continuous operation starting with a hot plate. Thisenables me to run plates direct from the plate forming rolls into my1mproved mill without loss of heat. The process is particularlyconcerned with hot rolling at least at the start as will. be understoodfrom the following specification. The plates are first indentedpreferably while hot by means of rolls having teeth arranged instaggered relation which nearly perforate the plate. The metal of thewebs at the bottom of the indentations thus formed is readily sev 'eredor broken and the indented material may be stretched'or expanded bysuitable mechanism. I prefer to indent the plates so that the thin websextend transversely across the plate and then I frac- 35 ture or severthe webs and expand the plates longitudinally by means of a set ofstretching rolls, each succeedmg pair of which has a greater peripheralspeed than the preceding pair. In some cases the indenting rolls willsubstantially sever the metal so that it can be stretched or expandedimmediately. In other cases the pressure of the first pair of expandingrolls may be sufficient to reduce the gage of the stock and break thethin webs. The fracture may be aided by locally chilling the webs orbending the plate. In some cases it may be desirable to allow the metalto partially cool before expansion. As the thin webs cool more rapidlythan the strands, the webs Wlll be relatively chilled and will fracturemore readily. It is also possible to cut or punch the thin webs and thismay be desirable in some cases.

Figure 1, is a diagrammatic plan view showing the arrangement of a millfor carrytooth 8.

ing out the invention. Fig. 2, is a diagrammatic side view of the rollsfor the system. Fig. 3, is a side view showing the indenting rolls of amill of my invention. Fig. 4, is a side .view of the expanding rolls.Fig. 5, is a plan view showing a fragment of the prodnot of one form ofthe indenting rolls. Fig. 6, is a view on the, same scale as Fig. 5showing portions of the peripheries of the indenting rolls with thematerial being operated upon. Fig. 7 is a section on the plane of theline X--X of Fig. 5. Fig. 8, is a fragment of the completed product ofthe process. Fig. 9, is a section as on line Y of Fig. 5 of the drawingshowing a more pronounced web.

In the preferred form of mill the rolls 1 and 2 indent the plate instaggered arrangement and the plate is then expanded by the pairs ofrolls 3, 34:, 4-5, 5 and 6, 6. Although the indented plate may bestretched directly from the rolls 1, 2, I prefer to locate and arrangethe expanding rolls so that the rolls 1, 2, will be subject to theindenting strains only. The succeeding pairs of expanding rolls may berotated at say 25, 50, 100 and 200 feet per minute respectively.

The lower roll 2 is preferably smooth and the length of the teeth onroll 1 is parallel with the axis of the roll, the cross section of eachtooth being as shown in end view at 7 and 8 in Fig. 6. The stock 9 isdented as at 70, 70 by teeth in the row of tooth 7 and as at 80, 80 byteeth in the row of The teeth in row 7 are spaced apart so as to leavebonds such as 71 between the grooves 70, 70 and the teeth in row 8 arearranged so as to leave bonds such as 81 between the grooves 80, 80. Thebonds 71 come opposite the center of the grooves 80 and the bonds 81come opposite the center of grooves 70. At the bottom of each groove isa web 82 relatively very thin and easily fractured or severed. The widthof this web will depend upon the shape of the indenting tooth.

In the process of indenting a plate the metal between the teeth iscompressed at the bonds and also at the strands .10 and 11 which connectthe bonds. This greatly improves the quality of the metal. The teeth 7and 8 may be formed in any suitable way as by nurling or milling.Nurling produces harder and tougher teeth.

Any suitable expanding mechanism may be employed but my complete processcon- Patented J an. 4, 1916.

templates a set of stretching rolls. When the rolls 3, 3 are relied uponto reduce the gage of the stock materially they may be made heavier thanthe other expanding rolls. The product of the indenting rolls is likelyto be somewhat thicker than the raw sheet before indentation and more orless rounded upon the upper surface of the strands and the rolling downby rolls 3, 3 flattens and broadens the tops of the strands and bonds,the plate having a less tendency to flow at the lower side which ispractically continuous as it comes in between the rolls. As the platepasses between. the succeeding pairs of stretching rolls it is graduallyexpanded to the form shown in Fig. 8 and may be at the same time rolleddown in thickness.

Obviously it is possible to obtain some of the advantages herein setforth by using rolls having their teeth arranged so as to groove orindent the stock longitudinally. After indentation, the expansion may beaccomplished laterally of the line of feed or in a vertical. plane. Themethod herein illustrated however, is preferred.

The material from the expanding rolls may be run onto a cooling table orcoiled on a drum 12. By giving the drum a greater peripheral speed thanthe rolls 6, 6 the material may be expanded and coiled under tension andinsures a uniform action and product. The plates may be taken from areheating furnace and a single indenting machine with transfer tablesmay supply a plurality of expanding machines.

I reserve the right to claim the entire mill for carrying out thecomplete process of indenting plates and expanding the same and theproduct thereof and also specifically-the indenting rolls and theproduct thereof in separate applications.

What I claim is:

1. The method of forming reticulated metal which includes indenting asheet in staggered arrangement while hot, fracturing the webs at thebottom of the indentations and expanding the sheet.

2. The method of forming reticulated metal which includes indenting andfracturing a sheet in staggered arrangement and expanding it while hotby stretching.

3. The method of forming reticulated metal which includes indenting asheet in staggered arrangement, rolling it down and thereby fracturingthe webs at the base of the .indentations and then expanding the sheet.

4. The method of producing expanded metal, comprising rollingindentations in a metal slieetwliile hot and by further rolling,reducing and expanding said indented sheet.

5. The method of forming reticulated metal which comprises indentingasheet and thereby forming strands between the indentations thicker thanthe original sheet, fracturing the web of metal at the bottom of theindentations and separating the thickened strands.

6. The method of forming a reticulated fabric which consists in forminga plurality of indentations in staggered arrangement to outline strandsand at the same time holding the metal between the indentations,fracturing the metal at the bases of the indentations and bending thestrands to form openings.

7. The method of forming a reticulated fabric which consists inindenting the sheet in staggered arrangement to form strands andsimultaneously compressing the metal between the indentations andafterward opening out the sheet.

8. A continuous method of forming reticulated metal from hot metalsheets which consists in rolling staggered indentations into the face ofa hot metal sheet trans versely of the line of feed thereof and therebydisplacing the metal away from such indentations to form transversestrands between the indentations and then stretching the indented sheetforwardly in the direction of feed thereof to thereby form an expandedfabric.

NORRIS ELMORE CLARK.

